In DM 1.3, a DM client (DMC) notifies a DM server (DMS) of a command execution result through a synchronization or asynchronization response (or report) mode when the DMC performs an execution command. The DMC selects one of the two modes. To enable the DMC to transmit an asynchronization response, the DMS needs to send an identifier of a command when transmitting the command. When the DMS does not transmit the identifier of the command, the DMC cannot transmit an asynchronization response to the command. That is, it is possible to notify the DMC that the DMC can reply to a specific execution command through an asynchronization response by sending the identifier of the command in DM 1.3. However, a standard of selecting one of the two response modes cannot be provided to the DMC and thus the DMC needs to autonomously select the synchronization or asynchronization response mode and reply to a command in the selected response mode.